Do Now
December 9, 2013
• PBIS Card out on desk
• Cornell Notes – Cell Cycle
• Question: How does your body grow
and repair itself?
Cells divide and reproduce
Cell Division
The Life of a Cell
Vocabulary Terms for Mitosis
• Asexual Reproduction – new organism is
formed from one parent cell
• Mitosis - cell division that ensures that each
daughter cell gets an exact copy of the mother
cells DNA
• Cytokinesis - division of the cytoplasm during
cell division
• Chromosomes -A doubled rod of condensed
chromatin
• Chromatid - one half of a duplicated
chromosome
• Centromere - area where the chromatid of a
chromosome are attached
• Chromatin - granular material visible within the
nucleus; consists of DNA.
• Spindle - a network of microtubules that forms
during mitosis and moves chromatids to the
poles
• Cell Equator - this is where chromosomes pair
up and attach to the spindle
Before we begin, we must learn about
chromosomes.
Chromosomes
• Humans have 46 chromosomes in their cells.
• Carry the material for your characteristics
• One chromosome has 2 chromatids
• Held together by a centromere
Cornell Notes
What is the
purpose for cell
division?
• To increase the number of
cells
• Causes multicellular
organisms to grow
Define Cell Cycle • The steps from one cell
division to the next.
What do cells do
in their life cycle?
List the steps of
the cell cycle.
• All cells must:
– Form
- Develop
– Grow
- Die
•
•
•
•
•
•
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
• Where the cell spend most
of
its
life
growing
(not part of Mitosis)
Interphase
Explain the
stages of
interphase
• G1: normal cellular
functions occur, cell grows
• S: DNA replicates, 2 copies
of each chromosome
• G2: cell prepares for
Mitosis, centrioles split
Centrioles
Prophase
Analyze what
occurs during
Prophase in
Mitosis
– Chromosomes are visable
– Sister chromatids form
– Nuclear envelope disappears
– Spindle fibers form from
centrioles
– Centrioles move to opposite
endes of cell
Metaphase
Analyze what
occurs during
Metaphase in
Mitosis
– Double-stranded
chromosomes line up in
the middle (equator)
– Spindle fibers attach to
sister chomatids at the
centromere.
Anaphase
• Each centromere divides as
sister chromatids are are
pulled to opposite sides of
the cell.
Telophase
• Chromosomes reach opposite
sides
• Nuclear envelope forms
• Chromosomes uncoil
• Spindle fibers disappear
Cytokinesis
• Division of the cytoplasm
• 2 genetically identical cells form
–“Daughter” cells
Videos
• http://unctv.pbslearningmedia.org/resource/tdc02.
sci.life.stru.dnadivide/mitosis/
• http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter
2/animation__how_the_cell_cycle_works.html
• http://www.youtube.com/watch?v=ZEwddr9ho-4
(mitosis dance)